LISTVIEW numerical column

Hi,
I have a column header in listview called number, and the value is numeric value. But display in the column not show in proper alignment:

Number
100
9
23

I want to show it in right alignment for integer or double as following:

Number
100
    9
  23

How to work on this?  Below is the code:  I have tried many ways still not be able to make it

int p = 10;

listviewitem.SubItems.Add(p.ToString ("###"));

Thanks for help